Why do women have orgasms? Most of the time, I'm so occupied with answering questions about why some women don't have orgasms that I rarely stop to think about why women do have orgasms. It's a good question, really. And sexual scientists typically don't agree on the answer. But I came across a couple of studies recently published in the Archives of Sexual Behavior that discuss an evolutionary explanation for the ever-elusive female orgasm.
Dr. Puts and colleagues conducted a review of the literature on the evolutionary function of female orgasm. There are two main evolutionary approaches to explaining female orgasm: the byproduct hypothesis and the mate-choice hypothesis.
The byproduct hypothesis states that female orgasm doesn't have a direct evolutionary function; rather, women experience orgasm because of men's adaptation to it. The idea is that men were given sensitive orgasmic penises to reward them for spreading their seed. And recall that everyone, regardless of being biologically female or male, is born with the same anatomical structure. For the first two months after conception, the genitals are undifferentiated. So because male and female genitals are developed out of the same structure, women also get the benefit of this pleasure reward. For more details on this, check out The Case of the Female Orgasm: Bias in the Science of Evolution.
The mate-choice hypothesis states that female orgasm has evolved to function in mate selection in order to better attract mates who will be invested long-term or to select higher quality sperm for higher quality offspring. A variety of studies have suggested that female orgasm increases the odds of getting pregnant. Interestingly, another recent study also published in the Archives of Sexual Behavior found that women who faked orgasm performed a greater number of mate retention behaviors than women who didn't fake orgasm, perhaps offering more evidence to support the mate-choice hypothesis.
The main argument against women's orgasm being explained by an evolutionary perspective is how infrequently it happens during intercourse. Most women require additional stimulation in order to climax during intercourse (usually in the form of clitoral stimulation), and you'd think that if it were adaptive, an orgasm would be a little easier to come by.
Additionally, compared to masturbation, penile-vaginal intercourse is pretty inefficient when it comes to producing an orgasm. If female orgasm were really an evolutionary adaptation, one would think the opposite would be true.
The main question I am left with (which is a common theme I find missing in most evolutionary explanations), is 'where is the pleasure?' Female sexual pleasure certainly isn't considered as an adaptation or an evolutionary function in itself. There is some evidence to suggest that female (and male) orgasm aids in pair-bonding through the release of the anxiety-reducing and calming hormone oxytocin, especially in women, but that's about as close as any of this literature gets to female sexual pleasure.
I'll conclude in a similar way the scientific article was concluded, by saying there is still a lot of additional work to be done in decoding the possible function(s) of female orgasm. I'm certain of one thing -- this won't be the last time sexual scientists disagree on the topic of female orgasm.
ALSO ON HUFFPOST WOMEN:
According to Dr. Jennifer Berman, co-founder of the Female Sexual Medicine Center at UCLA, orgasms increase your circulation, keeping the blood flowing to your genital area. This in turn keeps your tissue healthy!
Although it can't be considered an alternative to daily exercise, having an orgasm is a cardiovascular activity. "Your heart rate increases, blood pressure increases [and your] respiratory rate increases," says Berman. And because it's akin to running in many physiological respects, your body also releases endorphins. Sounds like a pretty fun way to work your heart out.
Feeling down in the dumps? An orgasm might be just what you need to pick yourself up. In addition to endorphins, dopamine and oxytocin are also released during orgasm. All three of these hormones have what Berman terms "mood-enhancing effects." In fact, dopamine is the same hormone that's released when individuals use drugs such as cocaine -- or eat something really delicious.
A little pleasure may go a long way towards a good night's rest. A recent survey of 1,800 women found that over 30 percent of them used sexual release as a natural sedative.
Having an orgasm not only works out your heart, but also your head. Barry Komisaruk, Ph.D. told Cosmopolitan that orgasms actually nourish the brain with oxygen. "Functional MRI images show that women's brains utilize much more oxygen during orgasm than usual," Komisaruk says.
One thing that Victorian practitioners may have been onto is that orgasms can work to soothe certain aches and pains -- namely migraines and menstrual cramps. (So now you know what to do next time you have a headache if you don't feel like popping an Excedrin.) According to Berman, the contractions that make up an orgasm can actually work to evacuate blood clots during your period, providing some temporary relief.
Most of our lives are so hectic that it's hard to even imagine being relaxed. However, it turns out that sexual release can double as stress relief. Not only do the hormones help with this task, Berman says that being sexual also gives our minds a break: "When we're stressed out and overextending ourselves, [we're] not being in the moment. Being sexual requires us to focus on one thing only."
There actually might be something to the idea that we "glow" after sex. The hormone DHEA (dehydroepiandrosterone), which shows increased levels during sexual excitement, can actually make your skin healthier.
Last but not least, when you know what it takes to make yourself orgasm, you may increase your emotional confidence and intelligence. "When you understand how your body works and ... [that it] is capable of pleasure on its own, regardless of your partner status, you make much better decisions in relationships," says Logan Levkoff, Ph.D., a sexologist and certified sexuality educator. "You don't look to someone else to legitimize that you're a sexual being."
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